Open path optical sensing system having an ultrasonic cleaner and method

Abstract

An open path optical sensing system having an ultrasonic cleaner. The system includes at least one ultrasound transducer which is configured to propagate ultrasonic waves across exposed surfaces of optical components of the optical sensing system. The ultrasonic waves create tiny vibrations on the exposed surfaces of the optical components which clean the surfaces of environmental pollutants and prevent environmental pollutants from accumulating on the surface. The ultrasonic waves may have a frequency that is substantially different than the modulation frequency of a modulated laser light beam that is generated by a laser of the open path optical sensing system. The surfaces of a plurality of optical components may be cleaned by the ultrasonic waves of a single ultrasound transducer. A plurality of ultrasound transducers may propagate waves on a single optical component.

Description

RELATED APPLICATION INFORMATION[0001]This application claims priority to provisional application Ser. No. 62 / 084,851 filed on Nov. 26, 2014, incorporated herein by reference.BACKGROUND[0002]Technical Field[0003]The present invention relates to optical sensing systems, and more particularly, systems and methods for cleaning open path optical sensing systems.[0004]Description of the Related Art[0005]Optical sensing systems are utilized for a wide range of applications including gas and particle sensing and detection. One type of optical particle sensing and detection is open path absorption spectroscopy. In open path absorption spectroscopy, an optical source and a receiver are placed in the same environment as a gas to be measured. A light, such as a laser or LED, is directed by the optical source directly through the gaseous environment. The different types of gases in the environment will cause the light to absorb at different wavelengths. The absorbed light is received by the rece...

AI Technical Summary

Benefits of technology

The patent describes a method and system for cleaning optical components of an open path optical sensing system that are exposed to environmental pollutants. This is achieved by positioning an ultrasound transducer near the surface of the components and propagating ultrasonic waves across the surface to clean it and prevent pollutants from accumulating on it. The technical effect is to improve the efficiency and lifespan of the optical sensing system by keeping it clean and free from environmental pollutants.

Problems solved by technology

A main disadvantage of open path absorption spectroscopy is that the surfaces of some optical components are exposed to environmental pollutants which lead to a degradation of the performance of the system.

For example, the optical components may exhibit a poorer reflection, poorer transparency or a sensor malfunction due to the environmental pollutants.

However, these systems have only provided marginal benefits with respect to the accumulation of pollutants.

However, the mechanical wiping mechanisms are susceptible to inadvertently damaging the optical components and may also affect the performance of the sensor.

Furthermore, the mechanical wiping mechanisms require continual replacement.

However, in these systems, the sensors are unable to function during the cleaning and drying periods.

The cleaning solution may also leave a residue which can degrade the performance of the optical system.

Furthermore, these systems require additional structures to operate, such as electrical power and a water supply.

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